LOS ANGELES—If you thought NASA's latest Mars landing was a nail-biter, get ready for a sequel.

The space agency on Tuesday announced plans to launch another mega-rover to the red planet in 2020 that will be modeled after the wildly popular Curiosity.

To keep costs down, engineers will borrow Curiosity's blueprints, recycle spare parts where possible and use proven technology including the novel landing gear that delivered the car-size rover inside an ancient crater in August.